Shock absorbing webbing



Oct. 17, 1950 E. A. NEFF sHocK ABsoRBING wEBBING Filed Nov. 27, 1946 4Sheets-Sheet 1 m6/a /f' awm Oct. 17, 1950 Filed Nov. 27, 1946 E. A. NEFF2,526,264

sHocx ABsoRBING WEBBING' 4 Sheets-Sheet 2 Oct. 17, 1950 E. A. NEFF2,526,264

SHOCK ABSORBING WEBBING Filed Nov 27, 1946 4 Sheets-Sheet 3 A I 7a2/@wwWf,

Oct. 17, 1950 E. A. NEFF 2,525,264

SHOCK ABSORBING WEBBING Filed Nov. 27, 1946 4 Sheets-Sheet 4 PatentedOct. 1.7, 1950 UNITED STATES PATENT OFFICE sSHcoKifiBs'oRBn'vG` WBBIN'GEdward` Neff', hicag, Ill. Application November 27, 194, Srial 712,627ze claims; (c1. efr-193i rlhis'invention relates to shock absorbingweb-r bing, more particularly to webbing comprising `at least two groupsof cords or threads one group.

'in flight as the parachute reduces the speed from that of fallingfreely to that determined by the open parachute, so the object my belowered to the ground at a relatively safe speed.

The sudden checking of the free fall causes a Very largev shock to beapplied tothe parachute canopy, shroud lines, and other suspensionelements which may result in tearing or rupturing. thereof. This, ofcourse, would allow the vobject being lowered, whether equipment orpersonnel,

to continue its free fall with consequent de-Y struction on impact withthe ground. In addi; tion to this serious situation, the shock followingnormal parachute opening is apt to be quite:L

painful to personnel using them and may even cause severe injury'. Theseconstitute some of the hazards of parachute use bringing about fearswhich must be overcome in training persons to use parachutes.Accordingly, it is a further object of the invention to provide improvedwebbing for use in parachute suspension means to reduce the shock ofparachute opening to a safe or not unpleasant Value.

It is a further object of theinvention to provide improved suspensionwebbing to absorb the shock of parachute opening.

It is a further object of the invention to provideimproved suspensionwebbing for absorbing the shock of parachute opening that'is efficientin operation and not bulky in size.

'In carrying out the invention in one form, webbing elongatable under apredetermined load is provided which comprises a group of transversefibers, a series'of longitudinal cords overlying the group of transversefibers yand being adapted to support a load greater than thepredetermined load, rand ka series of longitudinal threads binding thelongitudinal cords to the group of transverse fibers,r the bindingthreads being adapted to'break ata plurality of points in successionunder the predetermined load.

substantially along lines |'5|5 of Fig. 14'; andH For amore completeunderstanding of the ine' vention, reference may now be had to theaccompanying drawings in which Figi. l is a` plan View. of a section ofwebbing embodying the invention;

Fig. 2 isan edge view of the webbing shown in Fig. 1;

Fig. 3 is a plan view of a sectionv of webbing 'after use;

Fig, 4 is an edge view of the webbing shown in Fig; 3;

Fig. 5 is an inside view of the webbing takensubstantially-along lines5-5 of Fig. 2;

Fig. 6 is anl inside view of the webbing taken substantially along lines6-6 of Fig. 4';

Fig.1'7 is an enlarged plan view of a portion of the webbing shown inFig. 1;

Fig. 8= is a sectional view taken substantially along lines 8-8 of Fig.v'7;

Fig. 9- is an enlarged view of one element of the invention;

Fig.l 10 is an enlarged plan view of a modified form of the invention;

Fig. llV is a sectional view taken' substantially Referring tof thedrawings, the invention is shown in Fig. 'l as embodied inwebbing 2,0in'- cluding a series Yof transverse fibers 2l, a se; ries ofrelatively' longitudinal cords 2.2 anda series ofV relativelylongitudinal threads23' at-i taching cords 22 to ltransverse bers 2l",theseries of longitudinal threads 23 also being at:M

tacheds to transverse fibers 2l to forma base Las shown best in Fig. 5;

45% .The completedf webbingf may comprise two hal-ves attached togetherin any' convenient manner such as by stitching 211.` (Fig. 8) the two'halvesfbeing.identical with each other, and in the following'specification while the detailed de:

-' scription relates to only' oneA of the halves, it will be'understoodthat it hasapplication to both.

Referring: to' Figs. l, 7 and'8, it'willibe'lsee'n that the series ofcord's 22 'are laid` inl azigzag' or thereof by the longitudinal seriesof threads 23. The longitudinal series of threads 23 are stitched to orlooped around each of the threads in transverse series 2| at spacedregular intervals including both the longitudinal series of cords 22 aswell as the transverse fibers. In this manner the transverse series ofthreads 2l are held in their relatively closely spaced side-by-siderelation to form a base and the longitudinal series of cords 22 are heldin their sinuous pathways. The webbing consisting of a plurality ofrepetitive sections identical with each other, it is described withreference to a particular section such as may be seen between the crests25 and 26 of one of the cords (Fig. 7).

In the portion of the webbing shown in Fig, 7 lying approximatelybetween crests 25 and 2B there are transverse fibers 2l, 28, 29, 3|, 32,33, 34, 35, 3S, 3l and 38 which may be portions of a single continuousfiber as will be understood from Fig. 5. Also in the portion of thewebbing shown there are longitudinalcorcls 39, 4l, 42 and 43 (part ofseries 22) which are held in sinuous pathways on top of the transversefibers by the longitudinal threads 44, 45, 45 and 41 respectively (partof series 23). Considering the particular cord 4|, it is stitched to orlooped around the transverse bers by the two longitudinal threads 45 and43, thread 45 stitching cord 4| at its crests to transverse bers 2l, 23,35 and 38 respectively at points 48, 49, 5| and 52, and thread 46stitching cord 4I at its troughs to transverse bers 32 and 34 at points`53 and 54 respectively. As shown, the longitudinal threads stitchingthe crests of one longitudinal cord to the transverse fibers also stitchthe longitudinally adjacent troughs of the adjacent longitudinal cord tothe transverse fibers. Between the points 48 and 49 thread 45 isstitched to or looped around transverse fiber 28 and between points y5land 52 it is stitched to transverse ber 3l. In a similar manner each ofthe longitudinal cords is stitched to the transverse fibers to completethe webbing and as many repetitive sections as desired are made to giveany length and Width.

The webbing may be made on a well known at bed warp knitting machine inwhich a transversely reciprocable guide feeds and lays each transverseber across the bed of the machine. The desired number of longitudinalcords are longitudinally fed by individual guides also transverselyreciprocable so as to give the zigzag pathway to the cords, the cordsbeing fed on top of the transverse bers. The longitudinal threads arefed vertically downwardly and are held in individual guides which aremovable with a rotary type of motion so that the longitudinal threadsmay be wrapped around knitting needles moving vertically up and down.The knitting machine being well known, it is not believed necessary toillustrate it, since its manner of operation to produce the webbingshown will be clear to those skilled in this art from a consideration ofthe webbing alone. The loops of longitudinal threads, attaching orstitching the longitudinal cords to the transverse bers, being made on aknitting machine, are tightly formed around the respective cords andfibers as may be seen from Figs. l and 2. The relatively large loops ofFig. 7 are somewhat of an exaggeration to illustrate the webbingconstruction.

The principle embodied in the construction of the webbing in order toproduce shock absorbing is that of reducing speed gradually from a highvalue to a low value instead of suddenly. That is to say, in changingthe speed of a body gradually from a high to a low value a lesser forceis required to be exerted on the body or a lesser shock is produced.This phenomenon Y may be considered brieliy. A man falling freelybeforevhis parachute opens is falling with a high speed and thus he hasa large amount of kinetic energy. When the parachute is opened the speedof falling is checked, becoming a low value, and thus the man has asmall amount of kinetic energy. To reduce the kinetic energy hasrequired a force to be exerted over an interval of time or over acertain distance to produce the work necessary to absorb the energychange effected by the speed change. Thus if a large force is exertedover a small distance or a short time interval, the energy is reducedrapidly and the shock is great. However, if a much smaller force isexerted over a greater distance or a longer time interval, the same workis produced to reduce the energy but the shock is very much less. Inconventional webbing there is no provision for delaying the time inwhich the speed changes from its high to a low value when the parachuteopens. Consequently the speed change is rapid and the shock is great.The invention comprises webbing constructed so as to elongate or stretchout when the parachute opens, thereby spreading the reduction of speedfrom its high to a low value over a longer time interval, i. e., overthe distance the webbing elongates. Consequently the speed change isslower and the shock is much less.

An example may be considered. In order to support a man and hisequipment with a proper safety factor the suspension webbing of theparachute including the shock absorber webbing may be designed tosupport a maximum load of ve thousand pounds. A man and his equipmentmay weigh two hundred and fty pounds. The shock of ordinary parachuteopening may be of a value several times the weight of the man orconsiderably over one thousand pounds. But if the webbing is allowed togradually elongate over a period of time which, it will be understood,is still relatively short, the force exerted may be reduced to a valueapproaching the weight of the man or in the order of two hundred and ftyto three hundred pounds.

The elongation or stretching out of the applicants webbing isaccomplished by having two series of longitudinal members, a series oflongitudinal cords 22 which collectively are of suiiilcient strength tosupport the desired load with a proper safety factor, e. g. support amaximum of ve thousand pounds, and a series of longitudinal threads 23which are designed to break more or less collectively under a certainload such as, for example, two hundred andrfty or three hundred pounds.To bring these two elements properly into operation, the series oflongitudinal cords 22 have individually a greater free elongated lengththan the length of the webbing before breaking, and the eilective lengthof the longitudinal threads of series 23 individually are shorter thanthe longitudinal cords. The series fof longitudinal threads 23 isdesigned to break free elongated length and by binding the longiy gates,lthe longitudinal cords cause the longitu- A dinal threads to break at.different points.

To be more specic, consider Fig. 7, particularly longitudinal cord 4|and longitudinal threads 45 and 4B with the appropriate transversefibers.. Assuming that a load is applied .to the webbing under which itis placed under tension and as a result tends t elongate or stretch-outVthe cordsV of series 22 e. g. cord 4|, tend t0 straighten out(comparevFigs. l and .2; -Ia and |512) yAt the saine time, thelongitudinal threads of series 23 (i. e. threads45 and 46) are ,placed-under .tension and tighten their loops around the cords .and transversefibers. Thus, between points 49 and 5i, for examplegthe loop -in cord41| tends to straighten out but ,is ,prevented from so Idoing by thread45 between thesetwo points, since this portion of thread 45, includingits series of knitted loops or stitches, is of a lesser effective lengththan cord 4|. When the applied force Vbecomes great enough, thelongtitudinal thread :45, as well as the other longitudinal threads,including threads 44, 4B and 4l, break at corresponding points, thisoccurring for example at two hundred and fifty or three hundred pounds.'Suppose that thread 45 broke I.at point 55 where 'it is loopedgaroundtransverse fiber 35, and suppose thread 46 broke at point 56 where it islooped around transverse liber 36. The cord 4|, alo-ng with the other,longitudinal cords, straightens out the trough between vpoints 49 and5| since thread 45, having broken, no longer p revents this. The troughstraightens out until the lower portion thereof, between points 53 and54 is brought into eiTectiveness. Even though thread 46 broke previouslyat point .56, it isl looped around transverse ber 35, which, togetherwith the loop at point v54, holds the thread from slipping.Y Accordinglythread 46 is bound to cord '4| 'and under continued application of theload, tension is brought to bear' on thread 4,6 between points 5.3 and54 so that it breaks therebetween and allows cord il to straighten outlstill further, since another restraining force is removed.

Similar breaks occur in the other threads yncluding threads 44, l5 and41.

.'In asimilar manner, und-er continued application of the load, therebeinggripping of thread 4'5'by its loop with transverse fibers 3| and 29to prevent slipping,'thread 45, together with other threads Iatcorresponding'points, breaks between points 48 and49. In addition to itsbreaking previously inv cooperation with lcord 4| at point 55, thread45, preceding its breaking in .cooperation with cord 4| between points'dVand 1.49, has broken und-er the load in cooperation with cord 45Abetween transverse bers 32 and 34. While the initial breaking of thelongitudinal .threads of series 23 occurs under the :appliedload assuch, the continued breaking thereof occurs in succession at differentpointsfbecause the loops of the longitudinal threads around thetransverse .fibers eiect gripping therewith. Hence the longiltudinalthreads are bound to the longitudinal cords and slipping is prevented.The longitudinal :series of cords A2.2.

.'f-Ihe `construction `of loops in :the --threads of Iseries 23 betweenthe gripping points is also ffg :feet-ive to reduce the number oflongitudinal threads required in as much as looping increases thestrength of the threads over that of a single filament, i. e., loopingcauses three laments to exist between the transverse bers with aneffec-v tive strength of between two and three single filaments takentogether. The threads of series 23tmay be of any material having therequisite strength and dimensions and may, for example, be made of thematerial available under the trade name nylon.

The successive breaking having been described with reference to the onehalf of the webbing viewable in Figs. l and '7, reference to Figs. 2 and8 shows that the two halves of the webbing are stitched together byordinary stitching 24. Stitching 24 does not interfere with theoperation y-of the two halves together as has been described for onlyone half. In Figs. 3, 4 and 6 the ,fully elongated webbing is lshownafter an actual breaking test, Fig. 3 being an outside view and Fig. 6being an inside view showing the transverse fibers separated into groupswhich are Vspaced apart as the elongation necessitates.

In Fig. 9 one of the series of cords 22 is shown enlarged and it may bea cord comprising va braided tube made on a circular braiding machine.The requiste strength of such cords may be obtained by including anydesired number of individual laments made o f any substances having thesize and strength to meet design dimensions, suchfor example, as cottonor nylon. The cords of series 22 may be made in any other well knownmanner such, for example, as by twisting vfila-ments together.

The transverse fibers 2| forming the base may also be made of well knownmaterials and may be of cotton, hemp, nylon or the like.

Referring to Figs. l0 and ll, there is shown a section of webbingembodying amodified form of the invention, also including a series ofsinuous longitudinal cords laid over a base of transversely extendingbers, each longitudinal cord being attached to the transverse fibers bya longitudinally extending thread cooperating only with that particularlongitudinal cord. In Figs. 10 and ll, more particularly, there areshown the transverse fibers Overlying point 82, followed by thread 'Hbeing `looped.

around transverse fibers '58 and 59', following which thread 'H islooped around transverse fiber 6| and longitudinal cord 12 at point 83.`Similarly, longitudinal thread 'l1 is looped around.

transverseber 64 and Ylongitudinal cord l2 at ypoint 84, aroundlongitudinal -ber 6l! and transverse cord 12 at point 85, and aroundtransverse ber 69 and longitudinal cord l2 at point 86.. Longitudinalthread H is looped around the-trans- Lverse fibers and the cooperatinglongitudinal cord'.

at spaced points, between which the 'longitudinal thread'|'| is loopedaround only the transverse fibers, the longitudinal thread with itsloops in.

Aeffect extending along the axis or line of sym` metry of theconvolutions of the longitudinal cord.. The actual webbing when formedhas the transk Al/"erselbe'rs spaced' closely to each` other and thelongitudinal threads are tightly looped around them. However, even withthe loops, the eifective length of longitudinal thread 11 between the-points of attaching longitudinal cord 'l2 to the transverse i'ibers,for example, points 82 and 83, is less than the length of cord 'l2therebetween. This is an exemplication of the geometrical maxim that astraight line is the shortest distance between two points.

With the webbing constructed as shown in Figs. 10 and 11, theexplanation of operation is substantially the same as that given inconeection with the webbing shown in Figs. '7 and 8. Accordingly,longitudinal cords 1| to 'l5 and the other similar cords in the completewebbing are constructed collectively to support the load intended to becarried by the webbing. Moreover, longiztudinally extending threads '|6to 8| and the others within the fabric are designed to breakcollectively runder a load of predetermined value which is much lessthan the shock of an opening parafchute, for example, one having amagnitude of :two hundred and fty to three hundred pounds. ./Assuming aload or shock to be applied to the webbing, the longitudinal cords aswell as the "longitudinal threads tend to assume load. Inasmuch as theeffective length of longitudinal thread between two points such as 84and 85 is less lthan the length of longitudinal cord |2 between thosesame two points, the longitudinal thread .11 assumes the load rst.Thread being of lesser strength breaks at some point, for ex- ;ample, at89 between points 84 and 85. Similar breakages occur for the otherlongitudinally ex- Itending threads and the longitudinal cords lengthenout to their full length between these 'ltwo points. Since longitudinalthread is looped :around transverse fiber 65 and around transverse:lfiber 64 as well as cord l2 at point 84, the con- 'itinued applicationof the load will not cause slipping of longitudinal thread 'I1 but it isgripped by the bers around which it is looped. Consequently, thread llis bound to cord 'l2 which applies load thereto between points 83 and 84and other similar points As a result thereof, thread '|1 breaks at point8l between points 83 and 84, similar breakages occurring for the otherlongitudinally extending threads. This same process continues for thelongitudinal threads between points S82 and 83 and the webbing therebysuccessively elongates, each break occurring between approxi- -matelytwo hundred and fty to three hundred 4`pounds. After the longitudinallyextending threads have broken at all possible places and 'thelongitudinal cords have lengthenedY out to 4their full length, the loadis completelyl taken by .the longitudinal cords.

The longitudinal cords, the longitudinal threads, fand the transversebers illustrated in Fig. 10 may be of the same character as thosedescribed :ln connection with Figs. 7 and 8.

" Figs. 12 and 13 illustrate a longitudinal cord 88 which is amodication of the cord illustrated in lFig. 9. -of four compositeelements 89 twisted together, as :is shown in Fig. l2, to form thecompleted cord. Composite elements S9 (Fig. 13) comprise a singlelongitudinally extending filament 9| around -which is spirally wrapped asecond longitudinally extending filament 92, thereby increasing itsvlength. over filament 9|. Hence cord 88 comprises a series of twistedelements twisted together. Filaments 9| and 92 may comprise any desired`ifn'aterial and preferably may be made of nylon Longitudinal cord 88comprises a series Y g l which hasthe desirable properties of higheloi'ig.: tion under load.

Filament 92 is made suiiiciently large to be stronger than filament 9|,the strength of la-f ment 92 being such that it is sufficient to breaklament 9| when the two are attached together and force is exerted onfilament 92. For exami ple, if an element constructed as shown in Fig.ILS has a load exerted on it, filament 9|, being shorter, takes the loadfirst and breaks rst. Furthermore, with filaments 9| and 92 twisted asshown, and with a load exerted thereon to the extent that lament 9|breaks at some point, lament 92, of course, lengthens out somewhat in asmuch as filament 9| tends to slip within the spirals of filament 92.However, this slipping only goes on for a relatively short distancebecause the spirals of lament 92, tending to straighten out, grip lament9|. So, if a force is continued to be exerted, the lament 9| is heldwithin the spirals of filament 92 and breaks at a second point, sincefilament 9| is still shorter than rilament 92. Consequently, lament 9|breaks at a plurality of diierent points in a succession of steps.

Considering, now, that cord 88 is used as the longitudinal cords ineither of the webbings illustrated in Fig. 7 or 10, it will be clearthat when load is placed upon the webbing, the longitudinal threads etc.(Fig. 10) or 45, etc. (Fig. 7) will break rst with the resultspreviously described. However, after these longitudinal threads havebroken and the load is being assumed by longitudinal cords 88 which havestraightened out to their normal free elongated length (i. e.convolutions of Figs. l and 10 have straightened out), the twistedcomposite elements 89 tend to lengthen out further by virtue of the facthat filaments 92 being spirally wound are of greater free elongatedlength than filaments 9|. Accordingly, as longitudinal cords 88 furtherlengthen out under the assumption of load, laments 9| break at spacedpoints in succession thereby allowing laments 92 to straighten out thespirals therein and elongate, this process continuing until filaments 92are at their normal free length. Collectively, in completed webbing, thefilaments 9| are adapted to break under the load of two hundred and ftyto three hundred pounds. -By using a cord constructed as shown in Figs.12 and 13, an additional elongation of the webbing is obtained with theforce producing it remaining at substantially the same value necesasryto break the longitudinally extending threads initially.

Consequently there is a greater elongation produced for the same initiallength of webbing.

In Figs. 14 and 15 a webbing is illustrated embodying anothermodification of the invention. In this modication there is also a seriesof 90 of sinuously arranged longitudinally extending cords, a series 93of transversely extending fibers, and a series of longitudinal threads94 binding or looping the longitudinally extending cords to the seriesof transverse fibers. As shown'enlarged in Fig. 15, the longitudinalcords are taken in pairs, for example, cords 95 and 96. Cord 95 islooped to transverse bers 91 and 98 by the longitudinal lthe othertransverse cord to the subsequent two -to elongate a still greateramount.

adjacent transverse iibers followed by again looping the rstlongitudinal cord to the transverse fibers. Loops are formed in thelongitudinal cords between the adjacent pairs of transverse i'lbersiorexample, the loop in longitudinal cord 95 between the pairs oftransverse iibers 9?, 98 and |02, |03. In the interval between such twospaced prints the effective length of longitudinal thread 94 is lessthan the length of longitudinal cords 95 and 96. ,Y

Accordingly, when load is applied to the webbing, longitudinal thread 94breaks at some point within a spaced interval, and with the continuedapplication of the load the longitudinal thread does not slip, but isbound to the longitudinal cords through the various loops formedv-Consequently it breaksat a subsequent point, this procn ess continuingto allow the webbing to elongate ina plurality of steps as has alreadybeen described.

In any of the webbings illustrated the distance between the troughs andcrests of the various convolutions of the longitudinal cords may be soarranged that the final length of the webbing after use may be anydesired value, for example, approximately ity percent greater than theinitial length. v

In Fig. 16 the diagrammatic illustrations show the webbing in unextendedform, in partially extended form, and in completely extended form.

vIn Fig. 16a there is shown in unextended form a series of transverse.fibers with a single longitudinal cordy Idd tied to two longitudinallyeX- tending threads and |06 and to the transverse bers, the longitudinalthreads being tied .to the transverse fibers as well as to thelongitudinal cord. and the parachute is opened, the initial shock, ofcourse, through the longitudinal cords, such as cord |04, places a loadupon the threads, such as thread |06, which load breaks the longitudinalthread I 06 at a point |91. To break longitudinal thread |06, at point|01, checks the speed of the falling body a small amount inasmuch 'assome v of the energy is absorbed in breaking thread |06. Thus, thefalling body in continuing to fall moves a small amount slower. Theresisting force of the open parachute, however, continues to exert alarge force on the webbing with the yresult that cord |05 breaks atpoint |08 allowing the webbing To break -longitudinal thread |05, atpoint |08,. further checks the speed of the falling body since some ofAthe energy thereof ,is taken up in breaking thread |05. rlhis processcontinues until as shown in |51) a portion of the webbing is elongatedto the full' length of the cord lchwhereas the remaining portion of itis still tied by longitudinal threads |04 and |05. In Fig. 16e thelongitudinal threads |55 and |04 are broken at all possible points bythe shock of parachute opening and the webbing is at the full length ofcord |06.

While I have shown particular embodiments :of my invention, it will beunderstood, of course,

that I do not wish to be limited thereto since 'many modifications maybe made,` and I, therefore,l contemplate by the appended claims tovcover any such'modications as fall within the -true spirit and scope ofmy invention.

sively spacedV transversbers, a seresof longi- When an object is fallingfreely 10 tudinal cords overlying saidgroup of transverse bers and beingadapted to sustain the shocker parachute opening, and a series oflongitudinal binding threads, each one of -said' series of saidlongitudinal binding threads lforming a chain of stitches for bindingone or more of :saidlongitudinal cords to said group of transverserbers,

. said binding threads being adapted to break under the shockv ofpara-cute opening .to produce elongation of the webbing. g y 2. Webbingelongatable under a predetermined load comprising a group .of transverseliberata 'series of longitudinal cords overlying saidgroup of transversebersand beingy Aadapted to support a load greater thansaid-predetermined load-fand a series of longitudinal bindingl threads,eachone of said series of longitudinal lbinding threads forming a chainof stitches for binding one er -rnore of said longitudinal cords to saidgrouplolf transverse fibers, said bindingv threads v.being adapted vtobreak at a plurality of points ina succession' of steps under saidpredetermined load.

3. Webb-ing elongatable under a predetermined load comprisingl a Vgroupof Y transverse -`fibers forming a base, a series -of longitudinal.cords Yoverlying said -base and-adapted .to support a effective lengthof any of said bindingthreads between any two of said spaced pointsalonga `single cord being less than the length of the cord between the saidtwo spaced points. .A f 4. Webbing elongatable under a predeterminedload comprising a group of transverses,bersr forming a base, a series oflongitudinal cords overlying said base and adaptedtofsupport alqadgreater than said predeterminedfgload, each said cords being arranged ina zigzag manner, and .a series of binding threads adapted to vbreakunder said predetermined load, each one .of said series of bindingthreads forming a chainof stitches for binding said cords to saidtransverse bers at spaced points, the effective lengthof any one of saidbinding threads between any two of said spaced points along a singlecord being less than the length of the zigzag cord between the said twospaced points. l

5. Shock absorbing webbing for parachut s comprising a groupoftransverse bers forming a base, a series'of longitudinal cords over.-lying said base and adapted to sustainthe shock of parachute opening,said cords being arranged `in an irregularmanner whereby the lengthzqfpoints, the eiective length of any oneof said f binding threads betweenany two of said vspaced points of the cord bound thereby being less thanthe irregular length of the cord betweenzthe said two spaced points. I

' 6.y Shock yabsorbing .webbing `ici' parachutes omprising a groupoftransverse V'libere felini;A

ing a base, a 'series of Vlongitudinal.cords-overf lying said base andadapted to sustain theshock of parachute opening, and a-fseriesoibinding threads adapted to break under-fthe shockggof parachute opening,each of said Ybinding thv rads lformi/ng a chain of stitches for bindingsaid cords to said transverse fibers at spaced points, the length of anyone of said cords between any two of said spaced points being greaterthan the effective length of said binding thread between said two spacedpoints.

'7. Shock absorbing webbing for parachutes comprising a group oftransverse fibers forming a basea series of longitudinal cords overlyingsaid base and adapted to sustain the shock of parachute opening. saidcords having greater free extended lengths than the length of aycorresponding section of webbing, and a series of longitudinal bindingthreads adapted to break k-under the shock of parachute opening, each ofsaid longitudinal threads forming a chainof stitches for binding saidcords to said transverse fibers at spaced points, said cords beinglooped between said spaced points to give said greater free extendedlength` the effective length of any one of said binding threads betweenany two of said spaced points being less than the length of thecorresponding cord between said two points.

8. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse bers i forming a base. a series of longitudinalcords overlying said base and adapted to sustain the shock of parachuteopening, said cords being arranged in an irregular manner over said basewhereby the length of any one cord is greater than the length of acorresponding section of webbing, and a series of binding threadsadapted to break under the shock of parachute opening bound to each ofsaid transverse bers. each of said binding threads forming a chain ofstitches li'or binding one or more of said cords to certain ones of saidtransverse fibers at spaced points, the effective length of any one ofsaid binding threads between any two of said spaced points along asingle cord being less than the length of said single cord between saidtwo spaced points.

9. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse fibers forming a base. a series of longitudinalcords E overlying said base in an irregular manner adapted to sustainthe shock of parachute opening, yand a series of longitudinal bindingthreads adapted to break under the shock of parachute opening bound tosaid successive transverse fibers, each of said longitudinal bindingthreads forming a chain of stitches for binding said cords to certainones of said successive transverse threads at spaced points, theeffective length of any one of said binding threads between two of saidlspaced points of the corresponding cord being less than the length ofthe cord between said two spaced points.

10. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse iibers forming a base, a series of longitudinalcords overlying said base in an irregular manner adapted to sustain theshock of parachute opening, and a series of longitudinal binding threadsadapted to -break under the shock of parachute opening, each one of saidbinding threads forming a ychain of stitches looped around successiveones of said transverse fibers and looped simultaneously `around certainones of said transverse bers and said cords at spaced points, theeffective length of any one of said longitudinal threads between any twoadjacent ones of said spaced points being less than the length of thecorresponding cord between said two spaced points.

1l. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse fibers forming a base, a series of longitudinalcords overlying said base in sinuous pathways, said longitudinal cordsbeing adapted to sustain the shock of parachute opening, and a series oflongitudinal binding threads adapted to break under the shock ofparachute opening, each of said threads forming a chain of stitcheslooped around certain ones of said transverse bers and loopedsimultaneously around certain others of said transverse iibers and oneof said longitudinal cords at two points along the crest portion of thesinuous pathway and an adjacent one of said longitudinal cords at twopoints along the trough portion of the sinuous pathway, the effectivelength of any one of said longitudinal threads between any two of saidcrest portion points being less than the length of the correspondingcord therebetween.

l2. Shock absorbing webbing for para-chutes comprising a group ofsuccessive transverse fibers forming a base. a series of longitudinalcords overlying said base in sinuous pathways, said longitudinal cordsbeing adapted to sustain the shock of parachute opening, and a series oflongitudinal binding threads adapted to break under the shock ofparachute opening, each of said threads forming a chain of stitcheslooped around certain ones of said transverse fibers and loopedsimultaneously around certain others of said transverse fibers and oneof said longitudinal cords at spaced points substantially along the-center of the sinuous pathway, the eective length of said longitudinalthread between any two of said spaced points being less than the lengthof the cord therebetween.

13. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse iibers forming a base, a series of longitudinalcords adapted to sustain the shock of parachute opening overlying saidlbase in irregular pathways, said cords being arranged in groups of twocords each, and a series of longitudinal threads adapted to break undershock of parachute opening, each of said threads forming a'chain ofstitches looped simultaneously around two successive ones of saidtransverse fibers and one of the two cords of one of said groups of twocords and being also looped simultaneously around the adjacent twosuccessive ones of said transverse bers and the other of the two cordsof said one of said groups of two cords, the effective length of saidlongitudinal threads between successive loops around one of saidsuccessive two transverse bers and the corresponding one of said groupof two cords being less than the length of said corresponding cordtherebetween.

i4. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse bers forming a base, va series of longitudinalcords overlying said base in an irregular manner adapted to sustain theshock of parachute opening, each of said cords icomprising a series oflaments braided together, and a series of longitudinal binding threadsadapted to break under the shock of parachute opening, each of saidbinding threads forming a chain of stitches looped around successiveones of said transverse iibers and looped around Simultaneously certainones of said transverse fibers and said cords at spaced points, theeffective length of any one of said longitudinal threads between any twoadjacent ones offsaid spaced points being less than tudinal bindingthreads adapted to break under f the shock of parachute opening, each ofsaid binding threads forming a chain of stitches looped aroundsuccessive ones of said transverse fibers and looped aroundsimultaneously certain ones of said transverse fibers and said cordsatspaced points, the effective length of any one of saidlongitudinalthreads between any two adjacent ones of said spaced pointsbeing less than the length of the corresponding cord between said twospaced points.

16. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse fibers -forming a base, a series of longitudinalcords overlying said base in an irregular manner adapted to sustain theshock of parachute open-t i ing, each of said cords comprising a seriesof composite elements, and a series of longitudinal -binding threadsadapted to break under the shock of parachute opening, each of saidbinding threads forming a chain of stitches looped around successiveones of said transverse fibersv and looped around simultaneously certainones of said transverse fibers and said cords at spaced points, theeiective length of any one of said longitudinal threads between any twoadjacent ones of said spaced points being less than the length of thecorresponding cord between said two spaced points.

17. Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse fibers forming a base, a series of longitudinalcords overlying said base in an irregular manner adapted to sustain theshock of parachute open,- ing, each `of said cords comprising a seriesof composite elements twisted together and each composite elementincluding one filament and a second filament twisted therearound, and aseries of longitudinal binding threads adapted to break under the shockof parachute opening,

each of said binding threads forming a chain of stitches looped aroundsuccessive ones of said transverse fibers and looped around simultane- Yously certain ones ,of said transverse bers and said cords at spacedpoints, the effective length of any one of said longitudinal threadslbetween any l two adjacent ones of said spaced points being less thanthe length of thecorresponding cord between said two spaced points.

18. 'Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse fibers forming a base, a series of longitudinalcords overlying said base in an irregular manner adapted to sustain theshock of parachute opening,Y each of said cords comprising a series ofcomposite elements and each composite element includes two filaments oneof which is of greater free elongated'length than the second, filament,and a series of longitudinal binding threads adapted to break under theshock of parachute opening, each of said binding threads forming alchain of stitches looped around successive ones of said transverseiibers and looped around simultaneously certain ones of said transversefibers and said cords at spaced points, the effective length of any oneof said longitudinal threads between any two adjacent ones of saidspaced points being less than the length of the corresponding cordbetween said two spaced points.

1.9...Shock absorbing webbing for parachutes comprising a group ofsuccessive transverse bers forming a base, a series of longitudinalcords overlying said base in an irregular manner adapted to sustain theshock of parachute opening, each of said cords comprising a series oftwo filament elements one lament of which is adapted to break under theshock of parachute opening, and a series of longitudinal binding threadsadapted to break under the shock of parachute opening, each of saidbinding threads forming a chain of stitches looped around successiveones of said transverse fibers and looped around simultaneously certainones of said transverse fibers and said cords at spaced points, theeffective length of any one of said longitudinal threads between any twoadjacent ones of said spaced points being less than the length of thecorresponding cord between said two spaced points.

20. AShock absorbing webbing for parachutes comprising a' pair of groupsof transverse fibers forming bases, a pair of series of longitudinalcords overlying said respective base and adapted to sustainthe shock ofparachute opening, and a pair of series of binding threads adaptedto-break under said predetermined load, each of said binding threadsforming a chain of stitches binding respectively the cords of said pairof series of longitudinal cords to said transverse'fibers at spacedpoints, the length of any one of said cords Y between any two of saidspaced points being greater than the effective length of said bindingthread' between said two spaced points.

' EDWARD A. NEFF.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS

